Field of the Invention
The invention pertains to a color-picture-reproducing device, and to a method of producing same.
Description of the Prior Art
German Patent No. 28 06 436 and corresponding U.S. Pat. No. 4,243,735 disclose a method of producing the black edging around phosphor dots on the glass screen of a color picture tube. In that method, a slurry consisting of a bright sealing-glass powder, metal in oxidic form and a photoresist is sprayed on the glass screen. This slurry is then exposed through a mask and developed, the exposed parts are detached. In a subsequent annealing step at temperatures of between 350 degrees C. and 500 degrees C, the matrix thus formed is then changed into the desired black edging.
While the above method produced a satisfactory matrix, it was a costly and time-consuming process requiring first the disposition of material on the entire surface and then selective removal to form the matrix. Directly depositing the material in the shape of the desired matrix would be much more desirable. Screen printing of the matrix would have been an excellent solution to the problem; however, sufficiently fine wires for the printing screen were not available to provide a screen mesh fine enough to print matrix elements having a sufficiently narrow width.